Warp drier with air recirculating means



Aug. 26, 1947@ P. R. Rosa WARP DRYIER WI-'TH AIR RECIRCULATINGMEANS Filed Feb. 20, 1945 INVENTOR H104 /Pas ATTORNEY Patented Aug. 26, 1947 UNITED STAT-'Es PATENT oFFlcE Paul It. Rose, East Orange, N. J Applicatlll FebI-'ul'y 26, 1945, Serial N0. 578,845

This invention relates to a device for drying lengths of material.

One important application of the device is fory Another object of the invention is to provide an improved drying apparatus, which may be rapidly cooled when the supply of heated air is cut off.

Another object of the invention is to provide a method and apparatus for achieving more uniform drying of strip material.

Another object of the invention is drying apparatus which is operative without damage to material retained therein beyond the normal drying interval. f

Another object of the invention is. to make it possible to increase the speed-of travel of a length of textile material during a drying step, as for example the drying of warp and the sizing there- Another object of the inventionis to provide means safeguarding against the impairment of material due to oven drying.

Another object ofthe invention is to make possible the employment of air heated to within the range of from v200" to 600 F., or higher, to accelerate the drying of textile material.

Other objects of the invention will be in part obvious or in part pointed out hereinafter.

The invention accordingly consists in the features of construction, 4combinations of elements, arrangements of parts, and in the' several steps and relation and order of each of said steps to one or more of the others thereof, all as will be pointed out in the following description, and the scope of the application of whiclrwwill be indicated inthe following claims.

The invention will best be understood if the following description is read in connection with the drawings, in which,

Figure l is a side elevation of an embodiment of the invention; and l Figure 2 is a plan view taken on the line I-I Figure 1.

The term air is used herein in a broad sense, inclusive of any gas, or gases used for heating or cooling in accordance with the invention.

In accordance with the invention a length of to provide a drying chamber, and, .while it is travelling within said chamber, air heated above room temperature, and preferably well above 200 F. is brought into contact with the material to dry it, and means are provided for obtaining a flow of room al1l into and through said chamber to speedily exhaust the heated air from said chamber and to reduce the temperature therein to protect the material from over drying, as for example, in the event that the travel of the material stops for any reason. Various means such for example as fan means may be employed to exhaust the heated air from the chamber but preferably the treatment chamber comprises an elongated, substantially vertically extending passage from which heated air may be speedily exhausted when the supply of heated air is cut off, due to the difference in weight between the heated air and air at room temperature the speed of exchange of room air for highly heated air being aided if desired by means, such as said fan means. Preferably the length of material is passed through both an upward and a downward flight within said passage whereby its period of contact with the conditioned air within the passage is doubled and drying eiiciency is promoted since the material travels rst with and then against the flow of t air through said passage. As will be more fully explained means are provided for regulating the quantity of heated air brought into contact with the material, and the extent of the area within which heated air is brought into contact with the material.

As illustrated herein a length of material such, for example, as a length of warp I0, is shown passing into andout of a treatment chamber Il, embodying our invention, after being sized. The

chamber II comprises a central vertically extending portion A, and side portions B, and C, which serve as` by-passages for the recirculation and reconditioning of air from chamber A as will be more fully described. The central portion A has a bottom opening I2, and an exhaust port I3, at the top, so that an upward iiow of room air may be'obtained through said chamber when the supply of heated air is cut off. Extending substantially vertically from the bottom opening l2 toward the top exhaust port I3', the air distributing headers I4 and I5 are provided, being prefer- I ably of substantial height and of a width on the order of the Width of the material to be dryed,

' but of a lesser width than the width of the drythe material to be dried is passed into and out of ing chamberso that heated air brought into contactwith the material betweenthe headers may be circulated laterally around the ends of the headers as will be more fully explained.

It will be seen that the headers I4 and I6 provide between them a narrow channel P, thus carl rying further the channel-like character of cham ber II, and at the top of this channel, and preferably adjacentA to chamber exhaust port I9, a roller I6 is provided over which extends the material to be dried. As illustrated herein a length of material, in the form of a length ofA warp, is led upwardly within said channel P, after being sized and passed through the pairs of squeeze rolls I'I, and I8, of the sizing bath I9, and, after passing around roller I9, is led downwardly through channel P, in a. flight which is preferably parallel to 'its upward ilight, and out of bottom opening I2 and around guide roller 20 in the direction of the arrows. Both the upward 'and downward flights of the material are preferably divided into a plurality of planes as by splitterrolls 2 I, which serve to open the length of warp into a plurality oi' sheets, thereby separating adjacent warp threads and preventing them from sticking together while at the same time providing space between adjacent warp threads so that air can be brought into contact with the threads individually thereby facilitating drying the threads and the sizing thereon.

The headers I4 and I5 which are spaced apart in substantially parallel relation, are preferably slightly inclined to the vertical to facilitate tracking of the warp in the elongated channel formed between the headers.

As illustrated the chamber II is divided hori-` zontally by the floor 22, which is cut away to provide space for the headers, I4 and IiiV but otherwise divides chamber portion A horizontally so that air` can pass from below floor 22 to above iioor 22 only through passage P. 'I'he floor 22 may conveniently be a floor of a mill in which the drying chamber II is employed, the chamber extending partly below vand partly above said floor, and the latter being cut away to provide for the headers I4 and I6 and for the by-passing of air from passage l P and chamber portion A, through chamber portions B and C as will be explained. v

Chamber portion A is separated from chamber portions B and C, by the upwardly extending partitions 23 and 24 respectively. Between the top of the partitions 23 and 24 and the top of the chamber the dampers 25 and 26 are provided, which, when closed, serve to complete the partitions 23 and 24 respectively thus entirely separating the air space above iloor 22 in chamber portion A from the chamber portions B and C. Chamber portions B and C extend below the level of floor I22 and communicate with the headers I4 and I5. Each of the chamber portions B and C is provided with heater means H, and fan or air impellor means F, whereby when the dampers 25 and 26 are opened air is sucked into chamber portions B and C respectively, past heaters H, by the action of said fan means. The portion of the air thus diverted to chamber portions B, and C, is rst heated by the heaters H and then sucked into the fan means and forcibly delivered into y the said headers, and discharged therefrom into channel P, preferably through elongated ports or nozzles 21 and 28 respectively. It will be noted that, as illustrated, the nozzles o1' each header are spaced apart leaving laterally extending U-shaped recesses or channels'c between adjacent, outlet 'ports of the headers, adapted to lead v air around the ends of the headers to the inlets of chamber portions B and C. Heated air delivered into channel P through the headers I4 and I5, after being brought into contact with the flights of material within channel P will pass laterally in channels c and, a portion of it will be exhausted through exhaust port I3 which is always at least partially open, and a portion will be diverted into chamber portions B and C respectively when dampers 25 and 26 respectively are open, and redelivered into channel P and into contact with a length of material therein. Thus by regulation of dampers 25 and 26 a portion of the air which has been brought into contact with the material may be by-passed and recirculated through either or both chamber portions B and C.

The dampers 25 and 26 may conveniently be provided with handles, such as 25 illustrated in Figurel projecting beyond the side wall of the chamber for facilitating the manual operation of said damper means, and similar means may conveniently be provided for chamber exhaust damper 29 and the dampers 3I positioned within header I4.

As stated above the chamber exhaust port I3 isalways partially open, to exhaust moisture bearing air while the length of material is in motion, or to exhaust heated air when the material stops for any reason, and accordingly it is provided with a damper 29 which is preferably of a size to permit some ilow through the exhaust port even when it is in closed position. It will be readily seen that b-y` closing dampers 25 or 26 the supply of air to headers I4 or I5 may be cut 01T, and that by closing both dampers 25 and 2 6, and fully opening damper 29, the supply of air to the heaters and the fans may be entirely cut off thus cutting out the flow of heated air into channel P, whereupon the heated air will be speedily exhausted from chamber portion A, and particularly from channel P, and will be replaced by room airvfiowing upwardly into the chamber through bottom` opening I 2 Thus a protective flow of air at room temperature may be passed through channel P and the interior of the chamber may be speedily cooled at any time when needed to protect material present in the chamber from over drying as, for example, when for any reason the travel of the materia1 is stopped. Our device thus overcomes the disadvantage found in the operation of certain prior art dryers or slashers, particularly those heated by radiant heat, which can be cooled only very slowly and thus are liable to damage the material being dried by over exposing it to a temperature above the critical temperature for the material when the period of contact between the material and the air within the chamber is prolonged as it is for example when the travel of the cloth is stopped or the material is slowed down. For many textile materials for example, a heat of approximately F. is critical if the exposure is prolonged.

Becauseof the iiexibility of our device and the speed with which its internal temperature may be modied, or reduced below the critical tem- 4 perature for the material being dried, we are able to employ drying temperatures well above those which have heretofore been used for drying textile materials, including'lengths of warp and the like. Thus we are able to bring into contact with the length of material within channel P air heated in the range of from 200 F. to 600' F., or even higher, thereby making it possible to speed up the rate of .travel of the material during the drying step, andmaking possible -a corresponding speeding up in the successive steps of fabricating the cloth. g

In addition to protecting` the material from over-heatingby speedily Iremoving heated air from contact with the material being dried, we provide meansby which the drying operation may be continued without danger of damaging lthe material even when the material is advanced very slowly.

It is sometimes necessary to slow down travel of the material being dried without entirely stopping it. Specifically, in the treatment of warp in drying it after the sizing step it is undesirable to entirely stop the travel of the warp since the individual warp threads are in a sticky condition and tend to adhere together or to anything they touch, and if stopped would leave a deposit upon roller I6 which hardens and forms an encrustation likely to cause breakage of the warp threads. When individual warp .strands become broken it is accordingly the practice to reduce the speed of travel of the warp without altogether stopping it, and this reduced speed is referred to as the crawl, and to continue advancing the warp at the crawl while the ends` of a broken thread are being tied. f

For operation at reduced speeds a vertically extending partition 30 is provided within header I4, having between its top and the top of the header the dampers 3l which when closed serve together with partition 30 to close off a portion of the header --leaving only section L in communication with thefan means of chamber portion I B. As illustrated herein the fan means F are actuated `and controlled by motors M through the chain gears g and shafts s respectively. The motors M are preferably two speed motors so that when the travel of the material, in this case specifically a length of warp, is slowed to the crawl" the motors may be regulated lto actuate the fan F of chamber portion B at half-speed, and by closing dampers 3| in header I4 the air supplied by said fan means will be entirely diverted through section L of header I4. Thus only a limited quantity of heated air will be brought into contact with the material passing through channel P, and in only a limited area of the channel, thus preventing overdrying of the material during its movement at the crawl speed. To provide further control and prevent air sup-plied from section L from coming into contact with the warp on its second Aor downward flight a partition member I2a may be provided opposite section L, extending upwardly from the chamber bottom opening I2, between the upward and downward iiights ofthe warp.

It should be noted that the material to be dried, in passing into and out of chamber II contacts onlyA a single support means, roller IB, and that 66% or more of the moisture content of the warp will be removed from the warp prior to contacting the roller, the rate of reduction voi? moisture content of the warp being substantially greater during its upward iiight, when its` moisture Content iS greatest, than during its downward flight.

It will thus be seen that there has been proin which the various objects hereinabove set forth together with many thoroughly practical advantages are successfully achieved. As variousv possible embodiments might be made of the scope of the invention, it is to be understood that al1 matter hereinbefore set forth or shown in the accompanying drawing is to be interpreted as illustrative and not in a limiting-sense.

What I claim is:

1. Apparatus of the kind described which comprises a chamber communicating at the top with an exhaust flue and having a bottom port to admit a length of material to be dried, air. distributing headers extending from opposite sides of said bottom port upwardly through said chamber in the general direction of said exhaust ue each comprising ,a number of transversely extending elongated air ports spaced apart and thus forming laterally extending air chambers, the

ports of each header opening toward the other 1 header, ,means for supporting a length of material for travel through the channel defined by said headers, partition members within said chamber dividing the chamber into a central portion containing said headers and opposite side portions communicating twith the central portion above the upper ends of said headers respectively, means for admitting air into said central portion exteriorly -of said channel, means for controlling the volume of air admitted to said side portions respectively from said central portion, air heatingv means in said side portions respectively, and means in said side portions respectively for forcibly supplying air from said side portions into said headers respectively and through the ports of said headers into the vertically extending channel defined by said headers.

2. Apparatus of the kind described which comprises a chamber communicating at the top with an exhaust flue and having a bottom port to admit a length of material to be dried, air distributing headers extending from opposite sides of said bottom port upwardly through said chamber in the general direction of said exhaust ilue each comprising a number of transversely extending elongated air ports', the ports of each header opening toward the other header, means for supporting a length of material for travel through vided by this invention a method and apparatus mechanicalfeatures of the above invention andas the art herein described might be varied in various parts, all without departing from the the channel dened by said headers, vertical partition members within said chamber dividing it into a central portion containing said headers and opposite side portions communicating withl the central portion above the upper ends of said headers respectively, a, horizontally extending partition rnemlber extending across said central portion around said headers which are thus disposed partly above and partly below said partition, means for admitting air intosaid central'portion below said partition, means for controlling the volume of air admitted to said side portions respectively from said central portion, air heating means positioned in said sideportions respectively, means for forcibly supplying heated air from said side portions into said headers respectively, means for controlling the volume of air supplied to said headers, and means for varying the number of nozzles through which air is discharged from said headers into said channel.

3. Apparatusl of/the kind described which comprises a chamber having an entrance port t0 admit a length of material to be dried, an exhaust port, air distributing headers extending from opposite sides of said entrance port in the general direction of said exhaust port, each of said headers comprising a number of transversely extending elongated air ports spaced apart and. thus forming laterally extending air chambers, the ports of each header opening toward the other header, means for supporting a length of matechamber dividing the chamber into a central portion containing said headers and opposite side portions communicating with the central portion beyond the ends of said headers respectively, means for admittingy air into said central portion exteriorly of said channel, 'meansfor controlling the volume of air admitted to said side portions respectively from said central portion, air heating means vin said side portions respectively, and means in said side portions respectively for forcibly supplying air .from said 1 side portions into said headers respectively and through the ports of said headers into the said channel defined by said headers.

4. Apparatus of the kind described which comprises a chamber having an entrance port to admit a length of material to be dried, an exhaust port, air distributing headers extending from opposite sides of said entrar. ce port inthe general direction of said exhaust port, each oi said headers comprising a number of air ports, the ports of each header opening toward the other header, means for supporting a length of material for travel through the channel defined by said headers, partition members within said chamber dividing the chamber into a central portion containing 8 means for supporting a length of 4material for travel through the channel dened by said headers, partition members within said chamber dividing the chamber into a central portion containing said headers and opposite side portions communicating with-the central portion beyond the ends of said headers respectively, means for admitting air' into said central portion exteriorly of said channel, means for controlling the volume of air admitted to said side portions respectively from said central portion, air heating means in said side portions respectively, and means in said side portions respectively for forcibly supplying air i from said side portions into said headers respecsaid headers and opposite side portions communieating with the central portion beyond the ends of said headers respectively, means for admitting air into said central portion exteriorly of said channel, means for controlling the volume of air admitted to said side portions respectively from said central portion, air heating means in said side portions respectively, and means in said side portions respectively for forcibly supplying air from said side portions into said headers respectively and through the ports of said headers into the said channel defined by said headers.

5. Apparatus of the kind described'which comprises a chamber having an entrance port to admit a length of material to be dried, an exhaust port, air distributing headers extending from opposite sides of said entrance port in the general direction of said exhaust port, each 'of said headers comprising a number of air ports, the ports of each header opening toward the other header,

tively and through .the ports of said headers into the said channel defined fby said headers and means for creating a flow of air through said exhaust port to speedily'draw outside air into said chamber to replace the heated air therein whenever the operation of the device is stopped.

PAUL R. ROSE.

REFERENCES CITED The following references are of record in the file of this patent:

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